1. Field of the Invention
This invention relates to hoses and flexible lines for vacuum distribution, and specifically to such hoses having a vacuum conduit strengthened by integral buttresses imbedded in a plastic matrix and sheathed in a casing.
2. Description of the Related Art
Vacuum technology has applications in all processes carried out at less than normal atmospheric pressure. Industrial applications of vacuum technology range from manipulation of objects by use of suction cups to the deposition of integrated electronic circuits on silicon chips. Research laboratories, including medical research facilities, also make wide-spread use of vacuum technology. Electron microscopes and mass spectrometers are examples of research equipment requiring vacuum for their operation. Pumps of various designs and principles of operation provide the vacuum required for each application. Most applications, of course, require a conduit connecting the pump and the chamber or equipment to be evacuated; in many applications the conduit is a hose or other flexible line.
Hoses and other lines for vacuum distribution must of course be collapse-resistant. Various types of hose wall construction and different types of materials are used to furnish the strength necessary to avoid collapse. Making the walls stronger, however, generally reduces flexibility; flexibility is advantageous in many applications and necessary in some. The problem addressed by the present invention is how to make a hose for vacuum distribution which is both flexible and collapse-resistant.